Collapsible dam and damming method

ABSTRACT

An inflatable envelope type collapsible dam is made up of a plurality of inflatable envelopes one inside the other. The dam is mounted across a watercourse with the upstream edges of each of the envelopes anchored at substantially the same location. The dam may be constructed to a selected height by appropriately setting the pressures in each of the envelopes and each inner envelope operates to support a predetermined portion of the water pressure against their outer envelope or envelopes.

finite States Patent [191 Tabor COLLAPSIBLE DAM AND DAMMING METHOD [75]Inventor: Loring E. Tabor, Los Angeles, Calif.

[73] Assignee: N. M. Imbertson & Associates, Inc.,

Burbank, Calif.

[22] Filed: Dec. 6, 1972 [21] Appl. No.: 312,653

[52] US. Cl 61/30, 52/2, 61/27 [51] Int. Cl. E02b 7/04 [58] Field ofSearch 52/2; 61/1 F, 5, 27, 3O

[56] References Cited UNITED STATES PATENTS 3,067,712 12/1962Doerpinghaus 61/5 X 3,173,269 3/1965 lmbertson 61/30 3,355,851 12/1967lrnberston et a1 61/30 X 3,496,686 2/1970 Bird 52/2 FOREIGN PATENTS ORAPPLICATIONS 1,294,889 5/1969 Germany 61/1 F [111 3,834,167 51 Sept. 10,1974 6,506,682 7/1965 Netherlands 61/30 Primary Examiner-Mervin SteinAssistant Examiner-David H. Corbin Attorney, Agent, or Firm-Huebner &Worrel [5 7] ABSTRACT An inflatable envelope type collapsible dam ismade up of a plurality of inflatable envelopes one inside the other. Thedam is mounted across a watercourse with the upstream edges of each ofthe envelopes anchored at substantially the same location. The dam maybe constructed to a selected height by appropriately setting thepressures in each of the envelopes and each inner envelope operates tosupport a predetermined portion of the water pressure against theirouter envelope or envelopes.

4 Claims, 3 Drawing Figures PAIENI u 8591 men SHEET 10$ 2 PATENTEUSEP 10 m4 SHEET 2 [IF 2 BACKGROUND OF THE INVENTION The present inventionrelates to the damming of watercourses and the like. More particularly,the present invention relates to an improved method and improvedcollapsible dam structure for damming watercourses.

Heretofore there has been devised a collapsible dam consisting of asingle inflatable envelope formed from a suitable water impermeablesheet material which when inflated by liquid or .gas under sufficientpressure forms an effective dam across a watercourse. Such a collapsibledam is described in US. Pat. No. 3, I 73,269, which patent is assignedto the assignee of the present application.

While this prior art collapsible dam has been found satisfactory in mostsituations, the height of such a dam has been restricted by the strengthof the water impermeable sheet material available for making theinflatable envelope. Further, even though the sabotageof such a singleenvelope dam has proved to be extremely difficult, such a damnevertheless could be totally sabotaged by destroying the watertightness of its single envelope.

SUMMARY OF THE INVENTION It is, accordingly, an object of the presentinvention to provide an improved inflatable envelope type collapsibledam and method for damming which obviates the aforementioneddisadvantages of the prior art single envelope type dam.

It is further an object of the present invention to provide an improvedinflatable envelope type of collapsible dam and method of damming inwhich a plurality of envelopes are mounted one inside the other and thepressures of the envelopes are selectively set so that each innerenevelope supports a predetermined portion of the water pressure againsttheir outer envelopes.

In accomplishing these and other objects, there is provided inaccordance with the present invention, an inflatable envelope typecollapsible dam made up of a plurality of inflatable envelopes oneinside the other. The dam is mounted across a watercourse with theupstream edges of each of the inflatable envelopes anchored atsubstantially the same location in the watercourse. The pressures insideof the envelopes are selectively set so that each inner envelopesupports a predetermined portion of the water pressure against theirouter envelope or envelopes. Thereby, the dam may be built to anincreased height since a portion of the pressure on the material makingup the dam outer envelope is supported by the one or more innerenvelopes of the dam. Further since the dam has more than one envelope,it cannot be completely sabotaged by destroying the water tightness ofits outer envelope.

Additional objects of the present invention reside in the exemplarycollapsible dam and method of damming shown in the drawings andhereinafter particularly described.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of aninflatable envelope type collapsible dam according to the presentinvention mounted in a watercourse and inflated to dam the watercourse.

FIG. 2 is a perspective view of the watercourse of FIG. 1 illustratingthe recesses formed therein in which edges of the inflatable envelopesof the collapsible dam of FIG. 1 are anchored.

FIG. 3 is a view taken along the line 3-3 of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to thedrawings in more detail, there is shown in FIGS. 1 and 3 an envelopetype collapsible dam generally designated by the numeral 10. The dam 10is made up of an outer inflatable envelope II and one or more innerinflatable envelopes 12.

The dam 10 is mounted in a watercourse generally designated by thenumeral 13 and is shown in an inflated position for damming a waterheadformed by water 9 in the upstream portion of the water channel definedby the watercourse.

The dam envelopes 11 and 12 are fabricated from a pliable, nonexpandableand waterproof, or at least water resilient, sheet material in aconventional manner and may be constructed like the collapsible singledam envelopes described in US. Pat. No. 3,173,269.

The watercourse 13 may be an artificially constructed channel ormay be anatural water channel. For purposes of illustration, the watercourse I3is shown as being formed of concrete and having a substantially flat,smooth bottom surface 14 and two upwardly sloping inclined side walls15. In the watercourse 13 shown, the side walls 15 and bottom surface 14intersect along two substantially parallel lines 16. The lines ofintersection 16 extend the longitudinal dimension of the watercourse 13.2

As shown in FIG. 2, a plurality of transversely extending recesseshaving upwardly extending bolts 41 anchored therein for holding clampstructure are formed in the watercourse 13. Shown are an upstream recess20, a downstream recess 21 and one exemplary inner recess 22 locatedbetween the upstream and downstream recesses. The recess 20 is shownextending across the watercourse bottom surface 14 along a linesubstantially perpendicular to the lines of intersection 16 of the sidewalls 15 with the watercourse bottom surface 14. The recess 20 extendsup each side wall 15, preferably a short distance beyond theintersection lines 16.

A side recess 23 designed to permit the inner envelope or envelopes 12to collapse when deflated flatly against the watercourse side walls 15is formed along the watercourse side walls 15 to extend from a point ofintersection with the upstream recess 20 to a point adjacent thedownstream recess 21. The upstream portions 23a of the side recesses 23extend outwardly and upwardly from the intersection lines 16. Thedownstream portions 23b of the recesses 23 extend parallel to theintersection lines 16. The recesses 21 and 22 preferably extend parallelto the upstream recess 20 and are spaced apart appropriate distancesalong the longitudinal dimension of the watercourse 13. The innerrecesses 22, one of which is shown in FIG. 2, are formed to intersectwith the side recesses 23 and correspond in number to the number ofinner inflatable envelopes 12 included in the dam structure 10.

An outer row 24 of the bolts 41 are anchored in the watercourse bottom14 and side walls 15 to extend therefrom. The configuration of theportions of the outer row of bolting 24 on the watercourse side walls isdesigned to permit the outer envelope 11 to collapse flatly whendeflated against the watercourse side walls 15. The portion 24a of therow of bolts 24 extends transversely across the watercourse parallel tothe upstream recess 20. The portions 24b of the row of bolting 24 extendalong the watercourse side walls 15 along lines parallel to the upstreamportions 23a of the side recesses 23 to a pointdownstream from therecess 21. The downstream portions 24c of the row of bolting extendparallel to the intersection lines 16.

Conventional fluid supply means 30 are shown in FIG. 2 mounted in thewatercourse bottom surface 14 between adjacent ones of the transverselyextending recesses -22. These conventional fluid supply means includeconduits 31 for conducting fluid to and from the points at which theyopen in the bottom surface 14 and are operable to control the flow offluid to and from the inflatable envelopes mounted across thewatercourse 13.

FIG. 3 illustrates the outer envelope 11' mounted to extend between theouter row of bolting 24 and the downstream recess 21. The envelope 11 issecured in place in a conventional manner by clamp structure 40 of thetype described in US. Pat. No. 3,355,851. The clamp structure 40 issecured to the bolts 41 forming the outer bolting 24 and to the bolts 41in the recess 21. It is noted that US. Pat. No. 3,355,851 was issued tolmbertson et al. and is assigned to the assignee of the presentinvention. 1

One inner envelope 12, which is smaller in size than the predeterminedsize of the outer envelope 11, is illustrated secured in positionbetween upstream recess 20 and the inner downstream recess 22 adjacentthe recess 21. The envelope 12 is secured to bolts 41 in the same manneras the envelope 11 by use of clamps 40. It is noted that all therecesses20-23 are dimensioned so that the clamp structure 40 and theupper ends of the bolts 41 positioned therein are positioned below theflat bottom surface 14 of the watercourse 13.

Another inner envelope 12 is shown, for the purpose of illustrating aplurality of envelopes 12 within the outer envelope 11, in dashed linesin FIG. 3. This envelope 12 is of a predetermined size smaller than theenvelope 12 shown in solid lines. The envelope 12 shown in dashed linesis illustrated mounted to extend from the upstream recess 20 to anotherinner recess 22 shown in dashed lines. This other recess 22 is locatedupstream from the recess 22 shown in solid lines.

In operation of the plural envelope type collapsible dam 10, fluids,such as water 60 and air 61, are selectively pumped by means of thefluid supply means 30 into each of the closed regions 50-52 defined bythe fluid tight envelopes 11 and 12. By appropriately controlling thefluid pumped into each of the envelopes, the pressure levels in thechambers 50-52 can be selectively controlled to cause the dam 10 and itsenvelopes 11 and 12 to assume a selected configuration. It is noted thatthe pressures within each inner envelope the upstream edgesof theenvelopes 11 and 12 are mounted at substantially the same location inthe watercourse 13 that each inner envelope 12 supports the outerenvelope 11 from the watercourse bottom surface 14 to a selectedelevation thereabove. The elevation to which each inner envelope 12supports envelopes located outside thereof depends on the pressurelevels within each of the envelopes and the pressure applied to the dam10 by the water 9. As a result, the inner envelopes 12 support the outerenvelope 11 in the region in which the greatest water pressure is beingapplied. Consequently, since the outer envelope 1] is being reinforced,the dam structure 10 may be constructed to a height greater than wouldbe otherwise permitted by the strength of the material forming the outerenvelope 11. This is possible since the outer envelope 11 does not nowbear all the water pressure but the pressure of the water 9 is shared bythe inner envelopes 12 and divided between the anchor points of each ofthe upstream and downstream edges of the envelopes 11 and 12.

It is noted that by selectively controlling the pressures within theenvelopes 11 and 12 relativeto each other and the pressure of thewaterhead being dammed that the amount of pressure supported by each ofthe envelopes 11, 12 may be controlled in a predetermined manner.

Thus, there has been provided an improved collapsible dam and method ofdamming water in which a plurality of watertight envelopes are mountedone inside the other and the pressures of the envelopes are selectivelyset so that each inner envelope supports a predetermined portion of thewater pressure against its outer envelope or envelopes.

It is noted that the dam structure 10 is extremely difficult to sabotagesince for a saboteur to pierce all envelopes at the same time the lowerupstream portions of the envelopes would have to be punctured. Such anoperation would be extremely hazardous for a saboteur since he wouldhave to dive to the bottom of the upstream side of the dam and wouldconsequently be washed downstream if the dam collapsed.

It is noted that by mounting the bolts 41 and clamp structure 40 locateddownstream and inward of the row of bolting 24 in the recesses 20-23that the envelopes 11 and 12 of the darn 10 when deflated will not restupon the upper ends of downstream bolts 41. Thus, wear on the envelopes11 and 12 which could be caused by contact of the envelopes with thebolt ends is avoided. Additionally, it is noted that any suitable typeof control mechanism for controlling the pressures within the inflatabledam envelopes may be used, any suitable method for mounting. the damenvelopes in the watercourse may be employed, and the watertight damenvelopes may be constructed in any suitable manner. Suitable controlmechanisms, manners of mounting the envelopes and ways of forming theenvelopes are described in the aforementioned US. Pat. Nos. 3,173,269and 3,355,851.

Although I have herein shown and described my invention in what I haveconceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of myinvention.

1 claim:

1. A collapsible dam structure for damming a watercourse, comprising:

an outer inflatable envelope of a first inflated predeterminedcross-sectional size mounted to extend 3 8 34, l 67 5 6 across saidwatercourse, said outer envelope being 2. The invention defined in claim1, wherein strucoperable when inflated to dam said watercourse, turemeans recessed in said watercourse are provided and having upstream anddownstream portions relfor mounting the edges of said envelopes belowthe ative to the longitudinal dimension of said waterl i f id wat redges of said envelopes are mounted at substan- COUISe; u 5 3. A methodof damming a waterhead, comprising: atslgiaisgolrtieerlgpsgiljtgglgienlglgzpleltltggg fiirg gifg danf ming tge waterhgad with a firstinflatedhenvelope o a re etermme cross sectiona size avin an secondinflated predetermined cross-sectional size upstrgam portion facing Saidwaterhead i 8 g r 53rd first gg Concemnc trrerewrrg downstream portionspaced therefrom, said first a a r igi g gg g ifig z fig gzg f p g g q10 envelope having a first selected fluid pressure level therein; wlthand suppomllg Sald upstream supporting at least a portion of the insidesurface of of said outer envelope, fluid control means associl saidupstream portion of said first inflated envelope ated with saidenvelopes to independently inflate with a Second inflated envelo m m dth r and deflate said envelopes to appropriate pressure 5- d t t pe e d9" levels within said envelopes dependent upon the an cgncen 92 5d] iope g exterior water pressure against said darn structure, a P etermmeCrOS,SSecuOna Sma er an each of said envelopes include upstream anddownfirst envelopeismd Second envelope a Stream edges extending normalto the longitudinal second selected fiuld pressure level therein higherdimension of said watercourse, and the upstream than the Pressure levelor Sard first envelope' 4. The method defined in claim 3, includingsupporting the upstream portions of the first and second inflatedenvelopes with at least one other envelope of selected cross-sectionalsize by the same method that the first inflated envelope is supported bythe second inflated envelope.

tially the same location in said watercourse, and the downstream edgesof said envelopes spaced from said upstream edges are mounted in spacedapart locations one from the other along the longitudinal dimension ofsaid watercourse and said edges are generally parallel one with theother.

1. A collapsible dam structure for damming a watercourse, comprising: anouter inflatable envelope of a first inflated predeterminedcross-sectional size mounted to extend across said watercourse, saidouter envelope being operable when inflated to dam said watercourse, andhaving upstream and downstream portions relative to the longitudinaldimension of said watercourse; and at least one inner inflatableenvelope mounted within said outer envelope, said inner envelope beingof a second inflated predetermined cross-sectional size smaller thansaid first size and concentric therewith and having upstream anddownstream portions and when inflated including an upstream portion incontact with and supporting said upstream portion of said outerenvelope, fluid control means associated with said envelopes toindependently inflate and deflate said envelopes to appropriate pressurelevels within said envelopes dependent upon the exterior water pressureagainst said dam structure, each of said envelopes include upstream anddownstream edges extending normal to the longitudinal dimension of saidwatercourse, and the upstream edges of said envelopes are mounted atsubstantially the same location in said watercourse, and the downstreamedges of said envelopes spaced from said upstream edges are mounted inspaced apart locations one from the other along the longitudinaldimension of said watercourse and said edges are generally parallel onewith the other.
 2. The invention defined in claim 1, wherein structuremeans recessed in said watercourse are provided for mounting the edgesof said envelopes below the plain of said watercourse.
 3. A method ofdamming a waterhead, comprising: damming the waterhead with a firstinflated envelope of a predetermined cross sectional size having anupstream portion facing said waterhead, and a downstream portion spacedtherefrom, said first envelope having a firSt selected fluid pressurelevel therein; supporting at least a portion of the inside surface ofsaid upstream portion of said first inflated envelope with a secondinflated envelope mounted therein and concentric with said firstenvelope and having a predetermined cross-sectional size smaller thansaid first envelope, said second envelope having a second selected fluidpressure level therein higher than the pressure level of said firstenvelope.
 4. The method defined in claim 3, including supporting theupstream portions of the first and second inflated envelopes with atleast one other envelope of selected cross-sectional size by the samemethod that the first inflated envelope is supported by the secondinflated envelope.